Vestigial features are legion in the biological world:

	Wings of flightless birds
	Extra toe bones of hoofed animals
	Lesbian sex practiced by certain parthenogenetic lizards
	Solid-color equines having the genes for zebra stripes
	Flies sometimes growing legs in place of their antennae and four instead of two wings
	Baleen whale and cow fetuses having teeth later absorbed
	Cetacean hipbones
	Animals with forward-pointing eyes having sideways-pointing eyes as embryos
	Human toes and "wisdom teeth"
	Big hind legs of some four-legged dinosaurs
	Fused bones in many species (why originally separate?)
	Hollowness of the bones of some flightless birds (dodos, penguins, etc.)
	Aquatic animals breathing air: sea turtles, sea snakes, sea iguanas, 
	 crocodilians, penguins, seals, and cetaceans
	Fishlike tadpoles of frogs and toads; gill bars in embryos of land vertebrates
	Human-embryo tails
	The amniotic sac, a vestige of an eggshell
	Vestigial legs of some snakes
	One big lung and one small lung in some snakes
	Alternation of generation in plants; flowering plants are diploid, 
	 but still have a tiny haploid phase
	Flowers of self-pollinating plants
	Vestigial flower parts of non-flowering angiosperms, like grasses
	Mitochondria and chloroplasts in cells; these were apparently once separate cells, 
	 and they retain separate genomes and transcription/translation apparatuses.

/Loren Petrich, the Master Blaster
/lip@s1.gov